Fix signing-up page renders

What does this MR do and why?

Relates to: #404629 (closed)

When check_captcha calls render mehotd, which would skip set_minimum_password_length method which makes minimum_password_length undefined

pry(main)> RegistrationsController._process_action_callbacks.map { |c| c.filter if c.kind == :before }
=> [:check_captcha,
 :set_minimum_password_length, 
  ...]
 

Screenshots or screen recordings

before	after

How to set up and validate locally

See #404629 (closed)

MR acceptance checklist

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